proxyarp: Relax frame length limit for RA and NA

Only the NS frames should be checked to be long enough to cover all the
fields used in the NS data structure. This allows shorter RA and NA
frames to be processed for multicast-to-unicast rules.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>

src/ap/ndisc_snoop.c

@@ -91,11 +91,13 @@ static void handle_ndisc(void *ctx, const u8 *src_addr, const u8 *buf,
 	int res;
 	char addrtxt[INET6_ADDRSTRLEN + 1];
 
-	if (len < ETH_HLEN + sizeof(*msg))
+	if (len < ETH_HLEN + sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr))
 		return;
 	msg = (struct icmpv6_ndmsg *) &buf[ETH_HLEN];
 	switch (msg->icmp6h.icmp6_type) {
 	case NEIGHBOR_SOLICITATION:
+		if (len < ETH_HLEN + sizeof(*msg))
+			return;
 		if (msg->opt_type != SOURCE_LL_ADDR)
 			return;